I hope so vs I hope to

[IHerOI]

i will explain it to u as i had the same problem before
as mrs huda wrote
will u join the university ?
i hope to

I think your father will be better soon
i hope so

in the first sen. u can complete it by adding join
so u can say i hope to join

in the second sen. u cant say i hope to
as if u try to add a verb after "To" u won't be able to do that
so u use i hope so
in that case so replaces the whole sen.
so u can say i hope he will be better soon

يعني بالعربي بتجيب to لما تقدر تقول i hope to (a verb)
وبتجيب so لما تقدر تقول i hope (sent.)
ده اللي انا اعرفه برضو بعد ما فضلت الحكاية دي مضايقاني حوالي شهر